The present invention relates to a new and improved method and apparatus for use in the field of cataract surgery. More specifically, the present invention relates to a new and improved method and apparatus of forming an aperture in the anterior portion of the lens capsule of an eye.
A cataract impairs vision by clouding the lens of an eye. In a normal eye, the lens is clear and helps to focus an image on the retina of the eye. The lens must be clear for the retina to receive a sharp image. If the lens is cloudy from a cataract, the image received by the retina is blurred.
To eliminate a cataract with a known surgical procedure, a small incision is made in the cornea or sclera of the eye. A surgical instrument is inserted through the incision in the cornea and is used to form an incision in the anterior capsule of the lens of the eye. After this instrument has been removed from the eye, a forceps or other instrument is inserted through the incision into the anterior chamber. Forceps or a cystotome or bent small gauge needle is used to capture a portion of the lens capsule adjacent to the incision. These instruments are then moved to tear the lens capsule and form an aperture in the lens capsule.
A small probe is inserted through the incision in the cornea and the aperture in the lens capsule. The probe emits ultrasound waves which soften and break up the nucleus of the lens so that it can be removed by suction. The process may be referred to as phacoemulsification. After the natural lens has been removed, it may be replaced by an artificial lens.
Difficulty is sometimes encountered in tearing the lens capsule to form an aperture in the anterior portion of the lens capsule. The lens capsule is then manipulated with instruments and torn to form the aperture. The tearing motion can result in the formation of a tear having an undesirable configuration. Various methods and devices for use in forming an aperture in the anterior portion of a lens in an eye are disclosed in U.S. Pat. Nos. 5,135,530; 5,728,117; 5,792,166; 6,379,370; and 6,629,980.